/*
 * Copyright 2000-2016 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.intellij.util.containers;

import com.intellij.util.IncorrectOperationException;
import gnu.trove.TObjectHashingStrategy;
import org.jetbrains.annotations.NotNull;

import java.util.*;

// have to extend ArrayList because otherwise the spliterator() methods declared in Set and List are in conflict
public class OrderedSet<T> extends ArrayList<T> implements Set<T>, RandomAccess {
    private final OpenTHashSet<T> myHashSet;

    public OrderedSet() {
        this(ContainerUtil.<T>canonicalStrategy());
    }

    public OrderedSet(@NotNull Collection<T> set) {
        super(set.size());
        myHashSet = new OpenTHashSet<T>(set.size());
        addAll(set);
    }

    public OrderedSet(@NotNull TObjectHashingStrategy<T> hashingStrategy) {
        this(hashingStrategy, 4);
    }

    public OrderedSet(@NotNull TObjectHashingStrategy<T> hashingStrategy, int capacity) {
        super(capacity);
        myHashSet = new OpenTHashSet<T>(capacity, hashingStrategy);
    }

    public OrderedSet(int capacity) {
        this(ContainerUtil.<T>canonicalStrategy(), capacity);
    }

    @Override
    public boolean removeAll(@NotNull Collection<?> c) {
        boolean removed = false;
        for (Object o : c) {
            removed |= remove(o);
        }
        return removed;
    }

    @Override
    public boolean retainAll(@NotNull Collection<?> c) {
        boolean removed = false;
        for (int i = size() - 1; i >= 0; i--) {
            Object o = get(i);
            if (!c.contains(o)) {
                removed |= remove(o);
            }
        }
        return removed;
    }

    @NotNull
    @Override
    public List<T> subList(int fromIndex, int toIndex) {
        throw new IncorrectOperationException();
    }

    @Override
    public boolean contains(Object o) {
        return myHashSet.contains(o);
    }

    @Override
    public boolean addAll(@NotNull Collection<? extends T> c) {
        boolean result = false;
        for (T t : c) {
            result |= add(t);
        }
        return result;
    }

    @Override
    public boolean add(T o) {
        if (myHashSet.add(o)) {
            super.add(o);
            return true;
        }
        return false;
    }

    @Override
    public boolean remove(Object o) {
        if (myHashSet.remove(o)) {
            super.remove(o);
            return true;
        }
        return false;
    }

    @Override
    public void clear() {
        myHashSet.clear();
        super.clear();
    }

    @Override
    public boolean addAll(int index, @NotNull Collection<? extends T> c) {
        throw new UnsupportedOperationException();
    }

    @Override
    public T set(int index, @NotNull T element) {
        T removed = remove(index);
        add(index, element);
        return removed;
    }

    @Override
    public void add(int index, @NotNull T element) {
        if (myHashSet.add(element)) {
            super.add(index, element);
        }
    }

    @Override
    public T remove(int index) {
        T t = super.remove(index);
        myHashSet.remove(t);
        return t;
    }

    @Override
    public int indexOf(Object o) {
        @SuppressWarnings("unchecked") T t = (T) o;
        int index = myHashSet.index(t);
        return index >= 0 ? super.indexOf(myHashSet.get(index)) : -1;
    }

    @Override
    public int lastIndexOf(Object o) {
        @SuppressWarnings("unchecked") T t = (T) o;
        int index = myHashSet.index(t);
        return index >= 0 ? super.lastIndexOf(myHashSet.get(index)) : -1;
    }
}